Since a liquid crystal display (LCD) panel is not a self-luminous, a conventional LCD device typically employs a backlight module as a backlight. A light guide plate (LGP) is an important component in the backlight module, and can convert a point light source or a line light source provided by the backlight source into a surface light source.
The traditional light guide plate is typically of flat-plate type, and disposed in the backlight module only as a pure optical member. A structure of the backlight module known to inventors is shown in FIG. 1, and an optical film 2 and a light guide plate 1 are separately and individually fixed in the backlight module. The optical film 2 is limited by a step structure of a frame 3. A shortcoming of such a backlight module is that, the light guide plate 1 and the optical film 2 are separately and individually fixed, which will cause the relative displacement between them during vibration in subsequent processing, thus easily causing vibration friction and poor white spots.